Question

What is the internal structure of a leaf?

Answer 1

Internal structure of a leaf:

1. The leaf is the vegetative part of a plant, which performs the process of photosynthesis.
2. Outermost layer of the leaf: It contains cuticle which protects the leaf from excessive water loss and from breaking due to the force of the wind.
3. Below it, there is a layer called epidermis, which contains chlorophyll containing cells and pores for exchange of gases and water.
4. Beneath the epidermis, lies the layer of mesophyll cells which are compactly arranged.
5. Mesophyll layer of cells contain two types of cells i.e., palisade mesophyll cells and spongy mesophyll cells.
6. Lower epidermis is present below the mesophyll, which contains vascular bundles and stomata.
7. The pore like openings are the stomata which are surrounded by the guard cells, which regulate the opening of the stomata.
8. Guard cells open the stomata when they are turgid and close the stomata when they are flaccid.